Skiing the north face of Plewman, did a ski cut, did not get anything to move, just a bit of sluff. 3rd turn in I triggered a large slab on the December rain crust. The depth of the crown varied but I would estimate that it was 30cm at its deepest point. I was able to partially ski out of the avalanche on the skiers left. Everything seems to be quite touchy in the Rossland range and we noticed a few other slabs that were triggered. Definitely should not have been skiing anything steep. Did not notice any whumphing or cracking prior to the avalanche. Snow quality is good, but stay low angle! Large cornices are also another hazard.